On February 21, the news of a new outbreak of Crown pneumonia in the prison system in many places once again triggered public opinion. According to the Ministry of Justice Prison Administration Bureau, as of 24:00 on February 20, a total of five prisons in Hubei, Shandong and Zhejiang provinces have been infected by criminals, and there are no serious cases. Among them, Wuhan Women’s Prison in Hubei Province confirmed 230 cases, Hanjin Prison in Hubei Province confirmed 41 cases, suspected 9 cases, suspected 1 case of juvenile correctional center in Hubei Province, Shandong Province, Rencheng Prison confirmed 200 cases, suspected 10 cases, Zhejiang Province, Shilifeng Prison confirmed 34 cases, all of which are imported cases. Behind the surprising figures, the aggregation of infections is also of great concern. However, because of the special nature of the prison, its aggregation is not representative. On February 21st, the news of a new crown pneumonia outbreak in the prison system in many places once again triggered public opinion. According to the Ministry of Justice Prison Administration Bureau, as of 24:00 on February 20, a total of five prisons in Hubei, Shandong and Zhejiang provinces have been infected by criminals outbreaks, there are no serious cases. Among them, Wuhan Women’s Prison in Hubei Province confirmed 230 cases, Hanjin Prison in Hubei Province confirmed 41 cases, suspected 9 cases, suspected 1 case of juvenile correctional center in Hubei Province, Shandong Province, Rencheng Prison confirmed 200 cases, suspected 10 cases, Zhejiang Province, Shilifeng Prison confirmed 34 cases, all of which are imported cases. Behind the surprising figures, the aggregation of infections is also of great concern. However, because of the special nature of the prison, its aggregation is not representative. Why are there frequent aggregated outbreaks? In fact, for places that are densely populated and prone to frequent contact between people, aggregated outbreaks are prone to occur once infectious patients appear? For example, public transportation (e.g. airplanes, trains), families, schools (child care institutions), etc. The so-called aggregated cases of novel coronavirus pneumonia3 refer to a small group of people (which can be a family, a construction site or a unit, etc.) in which an aggregated outbreak is suspected and more than two people are found to have been confirmed to have novel coronavirus pneumonia”, and these people may be infected with each other as a result of close contact, or when they are together in the same environment. Hospitals and prisons, two of the most unexpected places for people to gather outbreaks, which undoubtedly gives everyone a wake-up call, with the arrival of the post-holiday work tide, how to learn from the experience, and do a good job in crowded places of protection measures, has been imminent. What to do in the event of a gathering outbreak? Remember these key points Infectious diseases, as the name suggests, are diseases that can be prevalent in the population, and it needs to have three basic links: the source of infection, the means of transmission and susceptible people. From the current situation, it seems that the population is susceptible to the new coronavirus, so it is especially important to control the source of infection and the means of transmission. Usually, after an outbreak occurs, the relevant staff will retrace the whole process of infection, and the local CDC/hospitals and other relevant medical institutions will formulate appropriate prevention and control programs to isolate infected patients. At present, a number of our sentinel hospitals have implemented health status screening and health tracking for healthcare workers, patient carers and administrative and logistic staff in inpatient wards and community health service centers, and conduct daily health surveillance on in-hospital staff to identify potential risks. In addition, to prevent more people from being infected, the hospital practiced strict hospital zone management. Strict temperature measurement, questioning and registration for entry and exit from the hospital area, strengthening the pre-screening and triage process in the outpatient department, and registering patients are all systematic and organized measures aimed at controlling the third key point in the transmission of CKP: the protection of susceptible populations. Therefore, it is crucial for susceptible people to protect themselves first and foremost.